/*
* The MIT License (MIT)
*
* Copyright (c) 2014-2015 Umeng, Inc
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.umeng.comm.ui.widgets;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.graphics.RectF;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.view.GestureDetector;
import android.view.GestureDetector.SimpleOnGestureListener;
import android.view.MotionEvent;
import android.view.ScaleGestureDetector;
import android.view.ScaleGestureDetector.OnScaleGestureListener;
import android.view.View;
import android.view.View.OnTouchListener;
import android.view.ViewTreeObserver;
import android.widget.ImageView;
/**
* 图片裁剪缩放视图
*/
public class ClipZoomImageView extends ImageView implements
OnScaleGestureListener, OnTouchListener,
ViewTreeObserver.OnGlobalLayoutListener {
public static float SCALE_MAX = 4.0f;
private static float SCALE_MID = 2.0f;
/**
* 初始化时的缩放比例，如果图片宽或高大于屏幕，此值将小于0
*/
private float initScale = 1.0f;
private boolean once = true;
/**
* 用于存放矩阵的9个值
*/
private final float[] matrixValues = new float[9];
/**
* 缩放的手势检测
*/
private ScaleGestureDetector mScaleGestureDetector = null;
private final Matrix mScaleMatrix = new Matrix();
/**
* 用于双击检测
*/
private GestureDetector mGestureDetector;
private boolean isAutoScale;
private int mTouchSlop;
private float mLastX;
private float mLastY;
private boolean isCanDrag;
private int lastPointerCount;
public ClipZoomImageView(Context context) {
this(context, null);
}
public ClipZoomImageView(Context context, AttributeSet attrs) {
super(context, attrs);
setScaleType(ScaleType.MATRIX);
mGestureDetector = new GestureDetector(context,
new SimpleOnGestureListener() {
@Override
public boolean onDoubleTap(MotionEvent e) {
if (isAutoScale == true)
return true;
float x = e.getX();
float y = e.getY();
if (getScale() < SCALE_MID) {
ClipZoomImageView.this.postDelayed(
new AutoScaleRunnable(SCALE_MID, x, y), 16);
isAutoScale = true;
} else {
ClipZoomImageView.this.postDelayed(
new AutoScaleRunnable(initScale, x, y), 16);
isAutoScale = true;
}
return true;
}
});
mScaleGestureDetector = new ScaleGestureDetector(context, this);
setOnTouchListener(this);
}
/**
* 自动缩放的任务
*
* @author zhy
*/
private class AutoScaleRunnable implements Runnable {
static final float BIGGER = 1.07f;
static final float SMALLER = 0.93f;
private float mTargetScale;
private float tmpScale;
/**
* 缩放的中心
*/
private float x;
private float y;
/**
* 传入目标缩放值，根据目标值与当前值，判断应该放大还是缩小
*
* @param targetScale
*/
public AutoScaleRunnable(float targetScale, float x, float y) {
this.mTargetScale = targetScale;
this.x = x;
this.y = y;
if (getScale() < mTargetScale) {
tmpScale = BIGGER;
} else {
tmpScale = SMALLER;
}
}
@Override
public void run() {
// 进行缩放
mScaleMatrix.postScale(tmpScale, tmpScale, x, y);
checkBorder();
setImageMatrix(mScaleMatrix);
final float currentScale = getScale();
// 如果值在合法范围内，继续缩放
if (((tmpScale > 1f) && (currentScale < mTargetScale))
|| ((tmpScale < 1f) && (mTargetScale < currentScale))) {
ClipZoomImageView.this.postDelayed(this, 16);
} else {
// 设置为目标的缩放比例
final float deltaScale = mTargetScale / currentScale;
mScaleMatrix.postScale(deltaScale, deltaScale, x, y);
checkBorder();
setImageMatrix(mScaleMatrix);
isAutoScale = false;
}
}
}
@Override
public boolean onScale(ScaleGestureDetector detector) {
float scale = getScale();
float scaleFactor = detector.getScaleFactor();
if (getDrawable() == null)
return true;
/**
* 缩放的范围控制
*/
if ((scale < SCALE_MAX && scaleFactor > 1.0f)
|| (scale > initScale && scaleFactor < 1.0f)) {
/**
* 最大值最小值判断
*/
if (scaleFactor * scale < initScale) {
scaleFactor = initScale / scale;
}
if (scaleFactor * scale > SCALE_MAX) {
scaleFactor = SCALE_MAX / scale;
}
/**
* 设置缩放比例
*/
mScaleMatrix.postScale(scaleFactor, scaleFactor,
detector.getFocusX(), detector.getFocusY());
checkBorder();
setImageMatrix(mScaleMatrix);
}
return true;
}
/**
* 根据当前图片的Matrix获得图片的范围
*
* @return
*/
private RectF getMatrixRectF() {
Matrix matrix = mScaleMatrix;
RectF rect = new RectF();
Drawable d = getDrawable();
if (null != d) {
rect.set(0, 0, d.getIntrinsicWidth(), d.getIntrinsicHeight());
matrix.mapRect(rect);
}
return rect;
}
@Override
public boolean onScaleBegin(ScaleGestureDetector detector) {
return true;
}
@Override
public void onScaleEnd(ScaleGestureDetector detector) {
}
@Override
public boolean onTouch(View v, MotionEvent event) {
if (mGestureDetector.onTouchEvent(event))
return true;
mScaleGestureDetector.onTouchEvent(event);
float x = 0, y = 0;
// 拿到触摸点的个数
final int pointerCount = event.getPointerCount();
// 得到多个触摸点的x与y均值
for (int i = 0; i < pointerCount; i++) {
x += event.getX(i);
y += event.getY(i);
}
x = x / pointerCount;
y = y / pointerCount;
/**
* 每当触摸点发生变化时，重置mLasX , mLastY
*/
if (pointerCount != lastPointerCount) {
isCanDrag = false;
mLastX = x;
mLastY = y;
}
lastPointerCount = pointerCount;
switch (event.getAction()) {
case MotionEvent.ACTION_MOVE:
float dx = x - mLastX;
float dy = y - mLastY;
if (!isCanDrag) {
isCanDrag = isCanDrag(dx, dy);
}
if (isCanDrag) {
if (getDrawable() != null) {
RectF rectF = getMatrixRectF();
// 如果宽度小于屏幕宽度，则禁止左右移动
if (rectF.width() <= getWidth() - mHorizontalPadding * 2) {
dx = 0;
}
// 如果高度小雨屏幕高度，则禁止上下移动
if (rectF.height() <= getHeight() - mVerticalPadding * 2) {
dy = 0;
}
mScaleMatrix.postTranslate(dx, dy);
checkBorder();
setImageMatrix(mScaleMatrix);
}
}
mLastX = x;
mLastY = y;
break;
case MotionEvent.ACTION_UP:
case MotionEvent.ACTION_CANCEL:
lastPointerCount = 0;
break;
}
return true;
}
/**
* 获得当前的缩放比例
*
* @return
*/
public final float getScale() {
mScaleMatrix.getValues(matrixValues);
return matrixValues[Matrix.MSCALE_X];
}
@Override
protected void onAttachedToWindow() {
super.onAttachedToWindow();
getViewTreeObserver().addOnGlobalLayoutListener(this);
}
@SuppressWarnings("deprecation")
@Override
protected void onDetachedFromWindow() {
super.onDetachedFromWindow();
getViewTreeObserver().removeGlobalOnLayoutListener(this);
}
/**
* 水平方向与View的边距
*/
private int mHorizontalPadding;
/**
* 垂直方向与View的边距
*/
private int mVerticalPadding;
@Override
public void onGlobalLayout() {
if (once) {
Drawable d = getDrawable();
if (d == null)
return;
// 垂直方向的边距
mVerticalPadding = (getHeight() - (getWidth() - 2 * mHorizontalPadding)) / 2;
int width = getWidth();
int height = getHeight();
// 拿到图片的宽和高
int dw = d.getIntrinsicWidth();
int dh = d.getIntrinsicHeight();
float scale = 1.0f;
if (dw < getWidth() - mHorizontalPadding * 2
&& dh > getHeight() - mVerticalPadding * 2) {
scale = (getWidth() * 1.0f - mHorizontalPadding * 2) / dw;
}
if (dh < getHeight() - mVerticalPadding * 2
&& dw > getWidth() - mHorizontalPadding * 2) {
scale = (getHeight() * 1.0f - mVerticalPadding * 2) / dh;
}
if (dw < getWidth() - mHorizontalPadding * 2
&& dh < getHeight() - mVerticalPadding * 2) {
float scaleW = (getWidth() * 1.0f - mHorizontalPadding * 2)
/ dw;
float scaleH = (getHeight() * 1.0f - mVerticalPadding * 2) / dh;
scale = Math.max(scaleW, scaleH);
}
initScale = scale;
SCALE_MID = initScale * 2;
SCALE_MAX = initScale * 4;
mScaleMatrix.postTranslate((width - dw) / 2, (height - dh) / 2);
mScaleMatrix.postScale(scale, scale, getWidth() / 2,
getHeight() / 2);
// 图片移动至屏幕中心
setImageMatrix(mScaleMatrix);
once = false;
}
}
/**
* 剪切图片，返回剪切后的bitmap对象
*
* @return
*/
public Bitmap clip() {
Bitmap bitmap = Bitmap.createBitmap(getWidth(), getHeight(),
Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
draw(canvas);
return Bitmap.createBitmap(bitmap, mHorizontalPadding,
mVerticalPadding, getWidth() - 2 * mHorizontalPadding,
getWidth() - 2 * mHorizontalPadding);
}
/**
* 边界检测
*/
private void checkBorder() {
RectF rect = getMatrixRectF();
float deltaX = 0;
float deltaY = 0;
int width = getWidth();
int height = getHeight();
// Log.e(TAG, "rect.width() = " + rect.width()
// + " , width - 2 * mHorizontalPadding ="
// + (width - 2 * mHorizontalPadding));
// 如果宽或高大于屏幕，则控制范围 ; 这里的0.001是因为精度丢失会产生问题，但是误差一般很小，所以我们直接加了一个0.01
if (rect.width() + 0.01 >= width - 2 * mHorizontalPadding) {
if (rect.left > mHorizontalPadding) {
deltaX = -rect.left + mHorizontalPadding;
}
if (rect.right < width - mHorizontalPadding) {
deltaX = width - mHorizontalPadding - rect.right;
}
}
if (rect.height() + 0.01 >= height - 2 * mVerticalPadding) {
if (rect.top > mVerticalPadding) {
deltaY = -rect.top + mVerticalPadding;
}
if (rect.bottom < height - mVerticalPadding) {
deltaY = height - mVerticalPadding - rect.bottom;
}
}
mScaleMatrix.postTranslate(deltaX, deltaY);
}
/**
* 是否是拖动行为
*
* @param dx
* @param dy
* @return
*/
private boolean isCanDrag(float dx, float dy) {
return Math.sqrt((dx * dx) + (dy * dy)) >= mTouchSlop;
}
public void setHorizontalPadding(int mHorizontalPadding) {
this.mHorizontalPadding = mHorizontalPadding;
}
}